The invention relates to an instrument for assessing the rigidity or stiffness of any structure and more specifically concerns a tooth stability monitor for assessing the rigidity of a tooth in the jaw of a patient as a monitor of periodontal disease.
In the past the usual practice to determine the stability of a tooth is based on the "feel" of the tooth during hand manipulation. This practice is subjective and prone to error.
The prior art also discloses in U.S. Pat. No. 3,943,913 apparatus and method for determining tooth mobility. In this disclosure a probe is fixed inside the patient's mouth such that the probe is touching the tooth under examination. Then the tooth is pushed and pulled manually by means of a manipulating tool and the resulting movement of the tooth is sensed by the probe. The disadvantages of this device are that it is time-consuming to fix the probe in the patient's mouth and it is prone to error because there is no way to determine the force applied to the tooth except by the feel of the operator and is therefore prone to error.
In addition, the prior art discloses in U.S. Pat. No. 4,470,810 an instrument that applies a single impulse to a tooth and then the resulting rate of movement of the tooth is measured. The disadvantages of this device are that since it is a single impulse device, frequency and amplitude effects cannot be measured and it cannot have pull, and push and pull modes of operation.
It is an object of this invention to provide an instrument for assessing the rigidity or stiffness of any structure.
Another object of this invention is to provide a simple, easy to use tooth stability monitor.
A further object of this invention is to provide a tooth stability monitor that does not depend on the feel of the operator.
Still another object of this invention is to provide a tooth stability monitor that does not require time-consuming preparations prior to the use of the monitor.
A still further object of this invention is to provide a tooth stability monitor that can measure the effects at different frequencies and amplitudes of the movement of a tooth.
Yet another object of this invention is to provide a tooth stability monitor that can have either push, pull, or push/pull modes of operation.
Other objects and advantages of this invention will become apparent hereinafter in the specification and drawings.